The Army has officially started fielding its newest combat helmet, the Next-Generation Integrated Head Protection System:
According to service officials, the NG-IHPS will provide soldiers with “increased ballistic and fragmentation protection” in a 40% lighter package compared to the earlier Integrated Head Protection System, which was first fielded in 2018 to replace the Advanced Combat Helmet and Enhanced Combat Helmet.
The first NG-IHPS units were fielded to around 2,000 soldiers assigned to the 1st Brigade Combat Team, 82nd Airborne Division, on Monday, the service said.
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Speaking to Army Times, Head Protection Team lead engineer Alex de Groot attributed enhanced protection of the NG-IHPS to the use of lightweight polyethylene instead of rigid and inflexible Kevlar material in the helmet’s construction, with the former dispersing energy on impact rather than shattering like the latter.
Garand Thumb took a look:
Improved resistance to impacts is always desirable, but most casualties are due to artillery, and helmets in general do not protect against shock waves.
But they protect against fragmentation from artillery munitions — airbursts, mortars, etc. This was indeed their original function. The modern helmet was first developed and popularized during WWI, which was the definitive artillery war.
When it comes to stopping power, we’ve come a long way since then. The ECH/IHPS/NG-IHPS can stop a 17-grain steel fragment at >4000 feet per second. (Which comes pretty close to the velocity of similarly-sized fragments at the very point of munition detonation.) The best of the WWI helmets might stop that same fragment at a little bit over 1000 feet per second. So the modern helmet is a >10x better kinetic energy sink, at least against steel fragments.
(Against heavier lead handgun bullets, the picture is less clear. Steel helmets tend to over-perform, as they present a hard ricochet surface for soft lead bullets, and modern composite helmets don’t do a very good job of managing shell deformation, even against fairly low-energy handgun threats.)
Against blast waves, it’s true that there has been no significant improvement. Really, the only way to manage that problem would be to implement closed-face helmets, like motorcycle helmets, which is a deeply unpopular notion.